Comet 3I/ATLAS will pass closest to Mars on October 3, 2025. It will come within about 28 to 30 million kilometers (approximately 0.19 AU) from Mars during this flyby. This encounter will be a unique opportunity for scientists to observe the interstellar comet using spacecraft orbiting Mars. The comet will be traveling inside Mars's orbit as it makes its closest approach to the Sun later in October 2025, but it is confirmed that 3I/ATLAS will not hit Mars or any planet in the solar system during this passage.